“It is not that we have a short time to live, but that we waste a lot of it”

And at the end:

“No one keeps death in view, no one refrains from far-reaching hopes; some men, indeed, even arrange for things that lie beyond life—huge masses of tombs and dedications of public works and gifts for their funeral-pyres and ostentatious funerals. But, in very truth, the funerals of such men ought to be conducted by the light of torches and wax tapers, as though they had lived but the tiniest span.” [As if a child had died]

Seneca, On the Shortness of Life